Office chair



FIG. 1 is a left, front perspective view of an office chair showing our new design;

FIG. 2 is a left, rear perspective view thereof;

FIG. 3 is a front view thereof;

FIG. 4 is a rear view thereof;

FIG. 5 is a top view thereof; and,

FIG. 6 is a left side view thereof. 

The ornamental design for an office chair, as shown and described. 